Legendary lunar and planetary observer Walter Haas (1917-2015) died on 2015 April 6. Haas was renowned for the skill, integrity, and intelligence he brought to the serious observation of solar-system objects. He also possessed effective organizational and leadership skills, which bore fruit in the founding and sustaining of the Association of Lunar and Planetary Observers (ALPO, 1947-), one of the outstanding organizations fostering meaningful amateur solar-system work. He was responsible for setting many observers on a life-long path of honing their observing ablities, and himself served an apprenticeship under William Henry Pickering, which gave him a filiation with the great observers of the 19th century. There was, however, nothing antique about the science he advocated.

Walter Haas had a long-standing relationship with both the Royal Astronomical Society of Canada, and the British Astronomical Association (BAA). His influential monograph "Does Anything Ever Happen on the Moon" appeared in the Journal of the Royal Astronomical Society of Canada in 1942, and he published many other papers with the RASC in the 1930s-1940s.

Among other honours he won the Amateur Achievement Award of the Astronomical Society of the Pacific in 1994, and the International Astronomical Union named minor planet 3853 Haas (1981 WG1) in his honour.

Walter Haas can be heard talking with David H. Levy on Let's Talk Stars in 2005.